Blood of human beings contain

Options

A. Fe
B. Mg
C. Co
D. Al

Explanation

**Step-by-Step Solution:**

1. **Understanding the Composition of Blood**: Blood is a vital fluid in human beings that performs several functions, including transporting oxygen and nutrients throughout the body.

2. **Identifying Key Components**: One of the primary components of blood is hemoglobin, a protein found in red blood cells.

3. **Function of Hemoglobin**: Hemoglobin's main function is to transport oxygen from the lungs to the tissues and carry carbon dioxide back to the lungs for exhalation.

4. **Metallic Component of Hemoglobin**: Hemoglobin contains a metal that is crucial for its function. This metal is essential for binding oxygen.

5. **Identifying the Metal**: The metal present in hemoglobin is iron, which is represented by the chemical symbol Fe.

6. **Conclusion**: Therefore, the blood of human beings contains iron (Fe).

**Final Answer**: The blood of human beings contains iron (Fe).

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